Used as a catalyst in petroleum refining and chemical synthesis, especially in the production of automotive exhaust catalysts. Serves as a precursor for cobalt oxide materials in battery electrodes and electronic ceramics. Employed in the preparation of cobalt-based pigments for glass and ceramics, providing a distinctive blue color. Applied in electroplating baths to deposit cobalt metal for wear-resistant coatings. Utilized in textile industry for dyeing and as a drier in paints and inks. Also used in analytical chemistry as a reagent for detecting certain compounds.